Signal box for train-signal systems



Feb. 7, 1928.

Filed May 10. 1920 QM t3 avwm'm EarlCSmffom Patented 'Z,

nairsn STATES;

PATENT OFFICE.

near. 0. s'rarronn, or-rHILanEL1mm, PENNSYLVANIA, assreivon r THE UNITED STA1ES TRAIN SIGNAL COMPANY, or PORTLAND, MAINE, A CORPORATION or MAINE.

Application filed May 10, 1920, Serial .No. 380,151.

My said invention relates to the details of construction of the signal box and-apparatus forming a part of the apparatus shown and briefly described in application No. 380,286, filed concurrently herewith by lVilliam E. Benn and George E. Davies, and it consists in various novel features thereof as will be hereinafter more fully described and claimed.

Referring to the accompanying drawings, which are made a part hereof, and on which similar reference characters indicate similar parts,

Figure 1 is a vertical section through the signal box, illustrating the apparatus there in in side elevation, and

Figure 2 a similar view through the signal box illustrating the apparatus therein partly in section and partly in front elevation.

In said drawings, the portions marked A represent the signal box casing, B the dial, and C the signal arm.

The casing, dial, and'signal arm are of the form illustrated or any other form that may be found appropriate or desirable.

Said signal arm is mounted on an arbor having a crank arm 11 thereon which is connected by means of a connecting rod '12 with a lever 13 pivoted in a bracket 14, its other end being positioned under the securing bolt 15 of an armature 16 of the magnet 17. Bracket 14 is mounted on an arm 18 in which is mounted a screw 19 adapted to come under the outer end of lever 13 to limit its downward movement. 7

A branch 20 of the air line leads to a chamber 21 in the top of a casing 22 in which is mounted a valve 23 adapted to lit a valve seat 24 around an aperture leading from the chamber 21 to another chamber 25., Said chamber 25 connnunieates by an aperture 26 with a pipe 27 on the outer end of which is mounted a signaling device, such as a whistle or sisser or other appropriate device.

The magnet 17 is connectedin electric circuit by means of wires 28 and 29. i

In operation, the electric circuit is normally closed and the armature 16 is in contact with the magnet, closing valve 26 and preventing air from passing from pipe 20- to pipe 27. The signal arm is also held in the position indicating safety. When, for

any reason,tl1e electric circuit is brokemthe magnet becomes de-energized, the armature 16 falls, operating through the lever 13, rod 12, and crank arm 11, to rotate the arbor l0 and turn the signal arm to the position of danger. At the same time valve 23 falls, air rushes from pipe 20 through the ports before indicated to pipe 27 and operates the signal at the end of said pipe.

Both an audible signal and a visible sig nal are thus provided operable immediately on the breaking of the electric circuit for any cause. When the circuit is closed and the magnet again energized, armature 16 is drawn upward, carrying with it plunger 30 which strikes the end of the valve stem and closes the valve against its valve seat with hammerlike action.

The weight of arm C, operating through its connections wit-h lever 13, nearly balances the weight of armature 16 so that comparatively little electrical energy is required to close the valve 24. The air pressure is likewise practically equalized on both sides of said valve so that no power is required to overcome air pressure in the operation of vention, what I claim as new and desire to secure by Letters Patent, is

1. In a signaling device, an electromagnet, an armature, a plunger rigid with the armature vertically slidable through the coil of the electromagnet, an audible signal operable by a compressed fluid, a valve supported by the upper end of the plunger whenclosed, said valve controlling the fluid supply to the signal, a visible signal, means for operating the signal including a rod connected thereto, a lever supporting the armature at one end and connected at the other to said rod, the parts being substantially balanced so as to require a minimum of electrical energy for operating them, substantially as set forth.

2. A signaling device comprising a casing, a stationary electromagnet in the cas ing, means for supporting the elect-romagnet, said supporting means containing a chainher and air passages connected thereto, an

audible signal connected to one of said passages, means for supplying air under pressure to the chamber through the other of said passages,a valve in the chamber to close the last named passage, a plunger to operate said valve, an armature on said plunger actuated by said electromagnet, a lever operated by said electromagnet when W deenergized, a link attached to said lever, a

rock shaft connected to the other end of the link, and a visible signal on the rockshaft adapted to be operated When the auflilolia signal is operated, substantially as set ort 1.

In Witness whereof, I have hereunto set EARL O. STAFFORD. 

